Design of mobile terminals may include a combination of functional, ergonomic, and aesthetic characteristics such as overall size, display size, ease of keypad use, availability of functions, appearance, and feel. Different designs may be selected to provide emphasis on desirable features that are reflected in device housing configurations.
Mobile terminals, such as cellular phones and personal digital assistants (PDAs), feature a variety of housing configurations. There are, for example, flip designs, “jack-knife” designs, and “candy bar” designs. Flip designs may include a flip portion mounted to an end of a housing with one or more hinges along the end of the housing. The operative faces of the flip and housing oppose each other when the flip is closed and are exposed when the flip is open. Jack-knife designs may include two housings, where one housing is rotatably mounted to the other housing with a pin-type connection made across the thickness of the housings, disposed at one end of the terminal when the housings are in the closed position. The operative face of one housing is always exposed, while the operative face of the other housing is hidden when the terminal is closed and is exposed when the terminal is open. Candy bar designs include a single housing, and are elongated, suggestive of a candy bar shape. Other designs include substantially planar, single housings. These designs may have a larger form factor than the other designs, but may also accommodate more keys or buttons.
Many mobile terminals currently include full “qwerty” keypads, with numeric keys hidden within the keypad and accessible for use by depressing a function key first. Such a design reduces the number of keys required, but may make it difficult to identify and use the numeric keys. Most mobile terminals that include such keypads do so with the substantially planar, single housing design, and have the keypad and display on the same operative face of the housing. Incorporating a display and a keypad into the same face, however, results in a screen size substantially smaller than the face, possibly with keys too small to easily use with one's fingers. Many terminals with full keypads also do not have the form factor of a phone that users are accustomed to and may prefer.